Network Errors on iPhone
Network errors
[Re-Titled by Moderator]
iPhone 7, iOS 15
To be able to use any SIM across the globe you must have "No SIM Restriction" against Network Provider Lock. Please refer to the pic below.
Carrier Lock:- Request your iPhone’s original Carrier to unlock your iPhone and if they agree and do it, then you may know the further process here --> How to unlock your iPhone for use with a different carrier ...
Device Unlocking Policies | Verizon Privacy Policy
Unlock a Phone or Device - AT&T Device Unlock Portal
Unlocking your Sprint device - T-Mobile
FAQs about unlocking your Sprint device
Unlock Your Phone for Spectrum Mobile